Conventionally, a monitoring system is known which captures images of a certain space using a camera device such as a monitoring camera, to monitor the space. At this time, atmospheric turbulence may occur in a captured image. Atmospheric turbulence is a phenomenon which occurs due to a change in characteristics of light transmitting media. Specifically, atmospheric turbulence is a phenomenon (Schlieren phenomenon) that occurs due to a change in a refractive index of a medium (air or water) which transmits light from a subject.
Atmospheric turbulence is so-called heat shimmer that occurs due to a difference in air density made by a temperature difference in the air when an image is captured outside on a hot day, for example. In addition, atmospheric turbulence occurs also when an image is captured underwater.
If a monitoring system detects, for instance, abnormalities from a captured video, the system may incorrectly detect atmospheric turbulence in an image as abnormalities, which is not preferable. In view of this, Patent Literatures 1 and 2, for instance, disclose an image processing device which can correct atmospheric turbulence in an image.